Industrial FLX Premix Watertube Boiler — Steam and Hot Water

R.F. MacDonald Co. services and sells boilers, pumps and accessories for commercial and industrial applications

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CB Boiler Model FLX Premix

CB Model FLX Premix

FLX Premix BoilerThe Model FLXPM Flextube boiler achieves best-in-class combustion performance with low emissions. Premix burner technology enables the boiler to attain <20 ppm NOx without FGR and <10 CO as standard on natural gas. The modulating burner control automatically adjusts the air/gas mixture for maximum efficiency and optimum turndown.

• Steam and hot water
• 75 to 250 HP
• Available to <9 ppm NOx, ultra-low CO
• Natural gas or propane fuel
• Premix burner technology
• Up to 5:1 turndown

Product Overview

The FLXPM integrates a servo-driven, fuel-input control valve with air-input control via a variable-frequency-driven fan for precise fuel/air ratio control.

Its compact design makes it easy to fit several units into a boiler room or into a larger hydronic system of condensing or non-condensing boilers. This multi-unit solution helps to divide the load more efficiently in a hydronic or in a steam process.

Because there is no requirement for FGR piping from the stack to the burner, it is easy to incorporate the FLXPM into a new or existing boiler system.


• Small footprint
• Ultra quiet
• Design protects against thermal stresses
• Hinged burner door for easy access
• 25-year warranty


• Lower Fuel Cost
• Lower Emissions


• Process Steam
• Industrial Process
• Building Heat
• Sterilization
• Hospital and Healthcare